It has not been a great six months for Jerry Kleiner and KDK restaurants.

First he closed Marche, which in its heyday was a top spot for viewing celebrities (I nearly collided with Martina Navratilova there one night). Then chef Jackie Shen departed from Red Light, the kitty-corner cousin to Marche, on Jan. 1.

Last week, the state forced the closure of Gioco, Kleiner's South-Loop restaurant, citing unpaid taxes. And now comes word that Red Light is closed, likely for good.

"It's run its course," Kleiner said of Red Light, one of the early KDK concepts that turned Randolph Street into a virtual restaurant row. "The concept is a little tired for us. To reinvest in the same concept...how many places make it for 15, 18 years?"

It seems strange, after 20 years, to imagine a Kleiner-less Randolph Street, but that's the nature of things, Kleiner said. "The people who packed Marche when they were 30 are 50 now," he said. "And until the economy hit 2 1/2 years ago, they were still thriving. But people aren't spending like that now. They're going for comfort food."

Gioco, however, is worth salvaging, Kleiner said.

"Gioco happens to be very profitable," he said. "Italian food has maintained its comfort level with people. Basically, Gioco has been carrying the other restaurants, waiting for the economy to clear up. Now we've sold off Opera (Kleiner's other South Loop property), which will take care of the tax problem. It'll all be cleared up, hopefully sooner than later, and Gioco will reopen without a doubt."

Kleiner also is part owner of Carnivale restaurant, which he says is thriving ("I wish I had more of those"), and has a piece of the popular Il Poggiolo in Hinsdale.

"I'm moving on to different things," he said. "I'm sitting with a chef right now, talking new concepts, things I'd like to do."